Oculis Holding AG released topline data from its phase 3 DIAMOND program evaluating OCS-01, an investigational eye drop, for the treatment of diabetic macular edema (DME)—and the results are less than stellar.
Yikes. Before we talk about that, let’s get a refresher on OCS-01.
Quick rundown for you:
What it is: A novel, high-concentration (15 mg/ml) formulation of dexamethasone utilizing Oculis’ OPTIREACH solubilizing nanoparticle technology.
- About this tech: OPTIREACH is a proprietary platform designed to enable drug formulation of non-invasive topical treatments (eye drops)
- How it does this: By improving lipophilic drug solubility—which is crucial for drug absorption, distribution, and overall effectiveness.
The patient recovery period: around 2 to 3 hours.
The intent: For this increased solubility to help OCS-01 achieve an extended amount of residence time on the eye surface (plus two key advantages). Check out a visual of how it works.
So, where did we last leave off with its clinical journey?
We most recently reported (in April) the final patient visit for that aforementioned DIAbetic Macular edema patients ON a Drop (DIAMOND) phase 3 program, which consists of two identical trials and 800+ patients:
- DIAMOND-1 (NCT05066997)
- DIAMOND-2 (NCT06172257)
See here for details on participants and setup (consisting of two stages and a 1:1 randomization).
And what are the studies evaluating?
The primary endpoint: change in best-corrected visual acuity Early Treatment Diabetic Retinopathy (BCVA ETDRS) letter score at Week 52.
Secondary endpoints:
- Percentage of patients with ≥15-letter gain in BCVA
- Change in central subfield thickness, as measured via optical coherence tomography (OCT)
Now to the new topline data—what should we know?
Importantly: The study failed to meet both the primary and secondary key endpoints in the studies’ second stage.
And regarding those secondary endpoints:
- For retinal thickness, Oculus noted “a substantial and persistent reduction with OCS-01 vs vehicle at all visits in DIAMOND-2 and at all visits except Week 52 in DIAMOND-1”
- The key secondary endpoint ( ≥15-letter gain in BCVA) was also not met in both trials
Definitely not what we wanted to hear … how about OCS-01’s safety data?
This area was the studies’ saving grace, as the eye drop was not only well-tolerated but also had an overall safety profile consistent with prior trials.
And regarding adverse events (AEs): There were no unexpected AE developments observed.
So how does this compare to prior data readouts from these trials?
Those results were overwhelmingly positive: The DIAMOND-1 study’s stage 1 not only met its primary endpoint but also demonstrated:
- A statistically significant improvement in BCVA ETDRS score (check out the numbers)
- A strong visual gain in the treatment arm
Check out more of those details, as reported in May 2023.
This definitely doesn’t bode well for any future FDA filing plans, does it?
Indeed, it does not. Prior to this data readout (as recently as April, in fact), Oculus shared its intent to potentially submit a new drug application (NDA) for OCS-01’s DME indication in Q4 2026.
Of course, this was entirely dependent on a positive data readout from the DIAMOND program.
So what’s the plan now?
In the company’s words: “Based on the results, at this time, Oculis does not plan to pursue an FDA regulatory filing for OCS-01 in DME.”
Oculus CEO Riad Sherif added that the company will be finalizing its review of the program’s data and shift focus to advancing other assets in its late-stage development portfolio.
… any specifics on this?
Most notably:
- Licaminlimab, a biologic eye drop, for dry eye disease (DED) treatment.
- Check out our prior coverage
- Privosegtor, a novel peptoid small molecule asset, for the treatment of optic neuropathies.
- See here for the latest on this FDA-designated (twice over, in fact) investigational therapeutic and ongoing phase 3 PIONEER program